US3684397A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary transmission device
Assignee: Individual
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Filing: 1970-06-23
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Granted: 1972-08-15
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Expires: 1990-06-23
Abstract
Abstract A rotary transmission for cooling fan drives including a friction clutch and a pneumatically operated ram controlling the clutch against spring loading, the compressed air supply being controlled in turn by a thermostat valve. To ensure that the fan will be driven if the air supply or valve fails the clutch is engaged by the spring and disengaged by the ram. The substantial spring loading is absorbed between a pair of abutments which rotate together and a closed axial force-transmitting loop prevents axial forces appearing on the external drive members. The device may be built into the hub of a self contained cooling fan, or may be in the form of a shaft drive unit with a stationary casing.
Inventors
- 👤 Arthur Ernest Henry Elmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:53
CPC Classifications
F; F16; F16D; F16D25/00; F16D25/08; F16D25/082; F01; F01P; F01P7/00; F01P7/02; F01P7/08; F01P7/081; F01P7/082; F01P7/085
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
316 words
A rotary fan assembly including at one end an input drive member provided with means for connection to a rotary driving element, a hub provided with means for attachment of fan blades thereto, said hub being capable of relative rotation and relative axial movement with respect to said input drive member, a clutch including two clutch members attached respectively to said input drive member and to said hub whereby axial movement of said hub causes engagement and disengagement of said clutch, said fan blades being so arranged that the axial reaction forces therefrom act in a direction to engage said clutch, a spring means arranged to exert an axial force between said hub and said input drive member in a direction to engage said clutch, said spring means acting on one of said members through a rotary thrust bearing, which in one operative condition of said clutch is subject to relative rotation, and in the other operative condition of said clutch is not subject to relative rotation, a fluid operated ram including a ram piston and a ram cylinder supported by said hub, and arranged to exert an axial force between said hub and said input drive member in a direction opposed to said spring means, to disengage said clutch, and means for admitting operating fluid to said ram via a fluid duct positioned at the axial end of said hub opposed to said input drive member, said assembly also including axial abutment means at opposite ends of said spring means, one of said abutment means acting against a part of said thrust bearing whereby both abutment means are capable of conjoint rotary movement, and means acting in one operative condition of said clutch to load said thrust bearing by the stress in said spring means, and in another operative condition of said clutch to relieve said thrust bearing of the stress in said spring means.
Claim 2
Dependent Claim
316 words
A rotary fan assembly including at one end an input drive member provided with means for connection to a rotary driving element, a hub provided with means for attachment of fan blades thereto, said hub being capable of relative rotation and relative axial movement with respect to said input drive member, a clutch including two clutch members attached respectively to said input drive member and to said hub whereby axial movement of said hub causes engagement and disengagement of said clutch, said fan blades being so arranged that the axial reaction forces therefrom act in a direction to engage said clutch, a spring means arranged to exert an axial force between said hub and said input drive member in a direction to engage said clutch, said spring means acting on one of said members through a rotary thrust bearing, which in one operative condition of said clutch is subject to relative rotation, and in the other operative condition of said clutch is not subject to relative rotation, a fluid operated ram including a ram piston and a ram cylinder supported by said hub, and arranged to exert an axial force between said hub and said input drive member in a direction opposed to said spring means, to disengage said clutch, and means for admitting operating fluid to said ram via a fluid duct positioned at the axial end of said hub opposed to said input drive member, said assembly also including axial abutment means at opposite ends of said spring means, one of said abutment means acting against a part of said thrust bearing whereby both abutment means are capable of conjoint rotary movement, and means acting in one operative condition of said clutch to load said thrust bearing by the stress in said spring means, and in another operative condition of said clutch to relieve said thrust bearing of the stress in said spring means.
Claim 3
Dependent Claim
46 words
A rotary fan assembly according to claim 1, in which said hub, clutch, input drive member, thrust bearing, spring means, abutment means, and ram, constitute a closed axial force-transmitting loop, whereby axial reaction forces from said ram and spring means are confined within said fan assembly.
Claim 4
Dependent Claim
48 words
A rotary fan assembly according to claim 1, in which at least one of said piston and cylinder elements of said ram is capable of rotary movement relative to said input drive member or said hub respectively, whereby relative rotation between said piston and cylinder elements is avoided.
Claim 5
Dependent Claim
35 words
A rotary fan assembly according to claim 1 in which said fluid duct for admitting fluid to said ram comprises a non-rotating compressed air supply line positionEd centrally on the rotary axis of said assembly.
Claim 6
Dependent Claim
47 words
A rotary fan assembly according to claim 1, including an axially movable bearing by which said hub is mounted on a part connected to said input drive member, and including sealing means whereby the ram operating fluid admitted to the ram is prevented from reaching said bearing.
Claim 7
Dependent Claim
70 words
A rotary fan assembly according to claim 5, including a sleeve within said hub, connected to one element of said ram and to said thrust bearing, and a hollow spigot connected to said clutch input drive member, and surrounding said sleeve with a clearance, said axially movable bearing surrounding said spigot, and said spring means and thrust bearing being positioned at least partly between said hollow spigot and said sleeve.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |